1 Corinthians 15:10 But by the grace of God I am what I am: and his grace which was bestowed upon me was not in vain; but I labored more abundantly than they all: yet not I, but the grace of God which was with me.
Every one of us are what we are in the natural by our birth, by our training, and by our experiences. We are also something by the grace of God. Because of this, it is not unjust of God to require anything of us. Whatever God requires, His grace enables us to do it and makes us enough or sufficient for the obligation or responsibility (Acts 1:8, Ephesians 2:10). God wants nothing empowered by us.
The work we do, there is grace for it. (See Acts 14:2-3.) I would not embark on any ministry or service without an understanding of grace, or you tend to do things in vain or in frustration to the grace of God. In the early church it was considered recommended and necessary equipment for fulfilling the work of God Acts 14:26; 15:40. God doesn’t call the equipped, He equips those He calls. All Christians are given gifts of grace for service (Romans 12:6) and no one is given grace to sit or to do nothing.